Influence of modified atmosphere packaging on the survival of Salmonella Enteritidis PT 8 on the surface of chilled chicken legs.

摘要

This study sought to determine whether low numbers of Salmonella in the presence of natural microflora will survive on the surface of chicken legs stored in 30% CO₂/70% N₂ and 20% CO₂/80% O₂. In 4 experiments, a total of 240 pieces of chicken leg were inoculated with Salmonella Enteritidis PT 8, a wildtype strain, resulting in initial concentrations of approx. 4 log, 2.5 log, 1.5 log and 0.5 log cells per piece and kept under the selected modified atmospheres for 14 days. Counts of Salmonella were determined by the MPN method at days 0, 3, 7, 10 and 14 of storage. No significant increases or decreases in Salmonella numbers were observed in 20% CO₂/80% O₂. In 30% CO₂/70% N₂ there was a significant decrease in cell numbers at days 10 and 14; however, this decrease was observed only in samples with an initial Salmonella concentration of 4 log and 1.5 log cells per piece. Even low numbers of Salmonella Enteritidis in the presence of natural microflora survived well on the surface of poultry stored at 3 degrees C in both modified atmospheres tested. Results suggest that when temperature abuse takes place, even products with low initial numbers of Salmonella may constitute a health risk for consumers.